User-mounted concrete screed

Abstract

A portable screed for working concrete and which is mounted on the user. The screed includes a variable length screed plate, a vibrator for the screed plate, a frame attached to the screed plate, a body harness connected intermediate the ends of the frame, and a balancing weight positioned so that the center of gravity of the screed is essentially coextensive with the center of gravity of the operator. The body harness is adjustable along the frame, and the frame may be adjustable as required to ensure that the center of gravity of the frame is positioned coextensively with the center of gravity of the operator so that the operator is not unbalanced by the screed.

What is claimed is: 
     
       1. A portable screed for working concrete as the screed is moved across the concrete, the screed being configured to be mounted on and piloted by a human being, comprising a. a screed plate for working concrete,   b. means to impart vibrations to the screed plate for tamping and leveling the concrete,   c. an elongated frame connected to one end to said screed plate,   d. a body harness,   e. means connecting said harness to said frame intermediate the ends thereof, and   f. balancing means connected to said frame for positioning the center of gravity of said screed at the vicinity of the connection of said harness to said frame, said balancing means including a weight attached to said frame adjacent the end thereof opposite to said screed plate such that said weight counterbalances said screed to thereby so position said center of gravity.   
     
     
       2. A portable screed according to claim 1 in which said means to impart vibrations comprises a vibrator secured to said screed plate. 
     
     
       3. A portable screed according to claim 1 in which said frame comprises a pair of spaced, parallel tubes connected at one end to said screed plate. 
     
     
       4. A portable screed according to claim 3 including a cross brace between said tubes and an operator's handle connected to said cross brace. 
     
     
       5. A portable screed according to claim 4 including switch means on said handle for controlling said means to impart vibrations. 
     
     
       6. A portable screed according to claim 3 including means to adjust the length of said tubes. 
     
     
       7. A portable screed according to claim 6 in which said means to adjust comprises a joint in each said tube, a connector spanning said joint and having a plurality of attachment positions, and means for securing said connector to said tube at said joint. 
     
     
       8. A portable screed according to claim 1 in which said body harness includes a waist belt and said connecting means includes a pivot pin between said waist belt and said frame. 
     
     
       9. A portable screed according to claim 8 including a pair of shoulder straps connected to said waist belt. 
     
     
       10. A portable screed according to claim 8 in which said frame comprises a pair of spaced, parallel tubes and said connecting means includes a sleeve mounted on and slideable upon each tube, and including a pair of said pivot pins, one said pin being affixed to each said sleeve. 
     
     
       11. A portable screed according to claim 10 including means releaseably securing each sleeve to each tube. 
     
     
       12. A portable screed according to claim 1 including a hinged joint in said frame to permit one portion of said frame to be disposed at an angle relative to another portion of said frame, said joint including means to lock said joint. 
     
     
       13. A portable screed according to claim 1 including means releasably connecting said frame to said screed plate. 
     
     
       14. A portable screed according to claim 13 in which said releasable connecting means comprises a keyway in said frame and a corresponding key on said screed plate, and including means to clamp said frame to said screed plate when said key is engaged in said keyway. 
     
     
       15. A portable screed according to claim 1 in which said harness includes a vertical support structure and shoulder straps for mounting said support structure on a user, and in which said connecting means includes a pivot pin extending between said support structure and said frame. 
     
     
       16. A portable screed for working concrete as the screed is moved across the concrete, the screed being configured to be mounted on and piloted by a human being, comprising a. a screed plate for working concrete,   b. means to impart vibrations to the screed plate for tamping and leveling the concrete,   c. an elongated frame connected at one end to said screed plate, said frame comprising a pair of spaced tubes and a cross brace between said tubes,   d. a body harness comprising a waist belt,   e. means connecting said harness to said frame intermediate the ends thereof, said connecting means comprising a sleeve slideably mounted on each said tube and a pivot pin affixed to each said sleeve and secured to said belt, and   f. balancing means connected to said frame for positioning the center of gravity of said screed at the vicinity of the connection of said harness to said frame, said balancing means including a weight attached to said frame adjacent the end thereof opposite to said screed plate such that said weight counterbalances said screed to thereby so position said center of gravity.